{
  "bibcode": "2004GCN..2681....1G",
  "body": "M. Gladders and E. Berger (Carnegie Observatories) report:\n                                          \n\"We imaged a portion of the 2.5-arcmin error circle of GRB 040827 (GCN\n#2672), centered on the XMM-Newton X-ray source (GCN #2678), with the\nPANIC instrument on the Magellan Baade 6.5-m Telescope.  A total of 36\nminutes were obtained in the Ks-band under good weather conditions with a\nseeing of about 0.55\".  Within the 10-arcsec XMM error circle we find two\nsources with a magnitude of Ks~19.8+/-0.2 mag (XMM-1) and Ks~19.4+/-0.15\nmag (XMM-2) compared to 2MASS.  The positions of the two source are\n(J2000):\n        RA=  15:17:01.43\n        DEC= -16:08:22.7        (XMM-1)\nand\n        RA=  15:17:01.35\n        DEC= -16:08:28.6        (XMM-2)\n \nSource XMM-1 coincides with the I-band source reported by Berger, Thompson\nand Krzeminski (GCN #2680), while source XMM-2 appears to be extended.  \nWe therefore conclude that XMM-1 is the likely optical/NIR afterglow of\nGRB 040827.  A comparison of the Ks- and I-band magnitudes indicate a\nspectral index beta~-0.5 typical of GRB afterglows.\"",
  "circularId": 2681,
  "createdOn": 1093660355000,
  "email": "eberger@ociw.edu",
  "subject": "GRB 040827: Detection of NIR afterglow",
  "submitter": "Edo Berger at Carnegie Obs  <eberger@ociw.edu>",
  "eventId": "GRB 040827"
}